Bathtub



FIG. 1 is a top plan view of a bathtub showing my new design;

FIG. 2 is a view in front elevation thereof;

FIG. 3 is a bottom plan view thereof;

FIG. 4 is a rear view thereof;

FIG. 5 is a side view thereof, the opposite side being identical thereto. 

The ornamental design for a bathtub, as shown and described. 